Three-dimensional display system with depth map mechanism and method of operation thereof

Abstract

A method of operation of a three-dimensional display system includes: calculating an edge pixel image from a source image; generating a line histogram from the edge pixel image by applying a transform; calculating a candidate line from the line histogram meeting or exceeding a line category threshold for a horizontal line category, a vertical line category, a diagonal line category, or a combination thereof; calculating a vanishing point on the candidate line; and generating a depth map for the vanishing point for displaying the source image on a first device.

What is claimed is: 
     
       1. A method of operation of a display system comprising:
 calculating an edge pixel image from a source image; 
 generating a line histogram from the edge pixel image by applying a transform; 
 calculating a candidate line from the line histogram meeting or exceeding a line category threshold for a horizontal line category, a vertical line category, a diagonal line category, or a combination thereof; 
 calculating a vanishing point on the candidate line; and 
 generating a depth map for the vanishing point for displaying the source image on a first device. 
 
     
     
       2. The method as claimed in  claim 1  wherein generating the line histogram includes calculating a Gradient-based Hough transform on the edge pixel image. 
     
     
       3. The method as claimed in  claim 1  further comprising:
 identifying a first vanishing line for the candidate line having a diagonal orientation; 
 identifying a second vanishing line for the candidate line having the diagonal orientation and non-parallel with the first vanishing line; and 
 wherein: 
 calculating the vanishing point for the intersection of the first vanishing line and the second vanishing line. 
 
     
     
       4. The method as claimed in  claim 1  further comprising:
 identifying a first vanishing line for the candidate line having a diagonal orientation; 
 identifying a second vanishing line for the candidate line having a horizontal orientation; and 
 wherein: 
 calculating the vanishing point for the intersection of the first vanishing line and the second vanishing line. 
 
     
     
       5. The method as claimed in  claim 1  further comprising:
 identifying a first vanishing line for the candidate line having a diagonal orientation; 
 identifying a second vanishing line for the candidate line having a vertical orientation; and 
 wherein: 
 calculating the vanishing point for the intersection of the first vanishing line and the second vanishing line. 
 
     
     
       6. A method of operation of a display system comprising:
 calculating an edge pixel image from a source image; 
 generating a line histogram from the edge pixel image by applying a transform; 
 selecting a line category threshold for a horizontal line category, a vertical line category, a diagonal line category, or a combination thereof; 
 calculating a candidate line from the line histogram meeting or exceeding the line category threshold for the horizontal line category, the vertical line category, the diagonal line category, or a combination thereof; 
 calculating a vanishing point on the candidate line; and 
 generating a depth map for the vanishing point for displaying the source image on a first device. 
 
     
     
       7. The method as claimed in  claim 6  wherein calculating the candidate line includes:
 identifying a local maxima of the line histogram for a horizontal line category, the vertical line category, the diagonal line category, or the combination thereof; and 
 assigning the line category threshold to a pre-defend value for the horizontal line category, the vertical line category, the diagonal line category, or a combination thereof. 
 
     
     
       8. The method as claimed in  claim 6  wherein generating the depth map includes:
 detecting a horizontal line; 
 calculating a first gradient map for the region above the horizontal line having an upper depth distribution; 
 calculating a second gradient map for the region below the horizontal line having a lower depth distribution; and 
 generating the depth map by combining the first gradient map and the second gradient map. 
 
     
     
       9. The method as claimed in  claim 6  wherein generating the depth map includes:
 detecting a first diagonal line; 
 detecting a second diagonal line intersecting of the first diagonal line and the second diagonal line in an upper region of the source image; 
 calculating a first gradient map having an isotropic gradient distribution with circular symmetry based on the vanishing point; 
 calculating a second gradient map having a rhombus-shaped gradient distribution centered on the intersection vanishing point with ninety degree symmetry; and 
 generating the depth map by combining the first gradient map and the second gradient map. 
 
     
     
       10. The method as claimed in  claim 6  wherein generating the depth map includes generating the depth map by combining a horizontal gradient map and a rhombus-shaped gradient map. 
     
     
       11. A three-dimensional display system comprising:
 a first storage unit configured to store a source image; 
 an edge detection module, coupled to the first storage unit, configured to calculate an edge pixel image from the source image; 
 a straight line search module, coupled to the edge detection module, configured to generate a line histogram from the edge pixel image using a transform; 
 a line detection module, coupled to the straight line search module, configured to calculate a candidate line from the line histogram; 
 a vanishing point calculation module, coupled to the line detection module, configured to calculate a vanishing point on the candidate line; and 
 a depth generation module, coupled to the vanishing point calculation module, configured to generate a depth map from the vanishing point for displaying the source image on a first device. 
 
     
     
       12. The system as claimed in  claim 11  wherein the straight line search module is configured to generate the line histogram by calculating a gradient-based Hough transform on the edge pixel image. 
     
     
       13. The system as claimed in  claim 11  further comprising:
 a vanishing line search module, coupled to the line detection module, configured to identify a first vanishing line having a diagonal orientation and a second vanishing line having a diagonal orientation and non-parallel with the first vanishing line; and 
 wherein: 
 the calculate vanishing point module is configured to calculate the vanishing point for the intersection of the first vanishing line and the second vanishing line. 
 
     
     
       14. The system as claimed in  claim 11  further comprising:
 a vanishing line search module, coupled to the line detection module, configured to identify a first vanishing line having a diagonal orientation and a second vanishing line having a horizontal orientation; and 
 wherein: 
 the calculate vanishing point module is configured to calculate the vanishing point for the intersection of the first vanishing line and the second vanishing line. 
 
     
     
       15. The system as claimed in  claim 11  further comprising:
 a vanishing line search module, coupled to the line detection module, configured to identify a first vanishing line having a diagonal orientation and a second vanishing line having a vertical orientation; and 
 wherein: 
 the calculate vanishing point module is configured to calculate the vanishing point for the intersection of the first vanishing line and the second vanishing line. 
 
     
     
       16. The system as claimed in  claim 11  wherein:
 the line detection module is configured to identify a local maxima of the line histogram for a horizontal line category, a vertical line category, a diagonal line category, or a combination thereof. 
 
     
     
       17. The system as claimed in  claim 16  further comprising a vanishing line search module, coupled to the line detection module, configured to calculate a first vanishing line and a second vanishing line. 
     
     
       18. The system as claimed in  claim 16  further comprising:
 a calculate first gradient map module, coupled to the depth generation module, configured to calculate a first gradient map for the region above the horizontal line having an upper depth distribution; 
 a calculate second gradient map module, coupled to the depth generation module, configured to calculate a second gradient map for the region below the horizontal line having a lower depth distribution; and 
 wherein: 
 the depth generation module is configured to generate the depth map from the first gradient map and the second gradient map. 
 
     
     
       19. The system as claimed in  claim 16  further comprising:
 a calculate first gradient map module, coupled to the depth generation module, configured to calculate a first gradient map having an isotropic gradient distribution with circular symmetry around the vanishing point; 
 a calculate second gradient map module, coupled to the depth generation module, configured to calculate a second gradient map having a rhombus-shaped gradient distribution around the vanishing point; and 
 wherein: 
 the depth generation module is configured to generate the depth map from the first gradient map and the second gradient map. 
 
     
     
       20. The system as claimed in  claim 16  further comprising:
 a calculate first gradient map module, coupled to the depth generation module, configured to calculate a horizontal gradient map; 
 a calculate second gradient map module, coupled to the depth generation module, configured to calculate a second gradient map having a rhombus-shaped gradient distribution around the vanishing point; and 
 wherein: 
 the depth generation module is configured to generate the depth map from the first gradient map and the second gradient map.